The discharge vessels of the low-pressure hot-cathode gas discharge light sources contain a filling comprising a rare gas and a mercury based additive. In the end parts of the discharge vessels there are electrodes equipped with two output terminals, the electrodes being sealed in the end part. The electrodes are covered with an emission substance of low escape energy, whereby the emission of the electrons from the surface of the electrodes and generating of the discharge arc is ensured. The electrodes of this kind are the oxide based cathodes. The emission substance is prepared by covering the emission surfaces by an appropriate carbonate and during the pumping step of production of the fluorescent lamp that carbonate covering layer is transformed into appropriate oxide by cathode breakdown. This is a well-known step of the technology.
After the pumping step the electrodes of the discharge vessel are formed further by an ageing process. During this process a basic point of the discharge arc can be formed on the covering oxide layer of the electrodes sealed in the discharge vessel. The ageing process results in required ignition and operation parameters of the gas discharge lamp, e.g. the fluorescent lamp. Thus, the process of ageing is carried out for preparing the low-pressure hot-cathode gas discharge light source to operating, i.e. for lowering the ignition voltage of the gas discharge light source, particularly fluorescent lamp to the required value and for providing the stabilization process of the electric parameters.
The process of ageing according to the art comprises the steps of preheating the electrodes of a gas discharge light source, applying to the preheated electrodes a voltage being equal with or slightly exceeding the burning voltage rating of the gas discharge light source, generating thereby the discharge arc by applying, if necessary at the first time auxiliary means for facilitating the generating process mentioned and maintaining the discharge arc. This cycle of operations, shown e.g. in the US-PS 2 977 176, lasting relatively long time, generally from 350 to 600 seconds, is repeated more times. The process disclosed in the US-PS 2 977 176 is proposed to be applied in systems for producing gas discharge light sources wherein the cycles described are repeated many times resulting in an ageing technology requirring about one hour time until completing.
The known solutions of the art applied in ageing the gas discharge light sources of specified kinds can be characterized by relatively long cycles and this is the general disadvantage of the recently known highly developed technology of producing gas discharge light sources, particularly fluorescent lamps. This technology ensures high efficiency by the output of the modern production lines can not be followed by the known equipment of ageing. The quantities of the gas discharge light sources produced by the highly developed kinds of the technology lines renders it necessary to assign great surface to the equipment capable of carrying out the ageing step.